Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the description's added value is the output semantics: a 0-100 estimate, a sample-size count of properties, and the explicit caveat that no geometry is returned. That 'values only, polygons elsewhere' warning is exactly the kind of behavioral detail annotations can't convey.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences with no filler, and the operational caveat about polygons is placed at the end where it reads as a follow-up instruction. Leading with the report/section placement is mild overhead but does help an agent recognize the tool's role.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema, so the description correctly spends its words on return values (the estimate range, the property count, absence of geometry). It stops short of describing the record shape or the join key needed to attach values to /shapes/mesh-blocks polygons, which is the one thing an agent would still have to guess.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0% and the description never mentions the sole parameter, not even to specify expected format or how ambiguous suburb names are resolved (state, postcode, exact match). Because suburb_name is largely self-describing this stays at minimum-viable rather than failing, but the description compensates for none of the coverage gap.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names the specific measure (share of investment properties that are negatively geared, 0-100) and the unit of geography (mesh block within a suburb), which is far more informative than the title alone. It does not explicitly contrast itself with the similarly named sibling properties_valuation_negative_gearing or suburbs_market_investor_concentration, so an agent must infer the difference.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied by locating the tool as the 'Negative gearing' map layer in the Market section of a suburb report, and it helpfully routes polygon needs to /shapes/mesh-blocks. However, there is no explicit guidance on when to prefer this over the non-map negative gearing sibling or the investor-concentration tool, and no stated prerequisites.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.